What you said so far is very interesting to me. How
do I become a Buddhist?

Once there was a man called Upali. He was the follower
of another religion and he went to the Buddha in order to argue
with him and try to convert him. But after talking to the Buddha,
he was so impressed that he decided to become a follower of the
Buddha. But the Buddha said:

"Make a proper investigation first. Proper investigation
is good for a well-known person like yourself."
"Now I am even more pleased and satisfied when the Lord says
to me: 'Make a proper investigation first.' For if members of
another religion had secured me as a disciple they would have
paraded a banner all around the town saying: 'Upali has joined
our religion.' But the Lord says to me: 'Make a proper investigation
first. Proper investigation is good for a well known person like
yourself."
MII 379

In Buddhism, understanding is the most important thing and understanding
takes time. So do not impulsively rush into Buddhism. Take your
time, ask questions, consider carefully, and then make your decision.
The Buddha was not interested in having large numbers of disciples.
He was concerned that people should follow his teachings as a
result of a careful investigation and consideration of facts.

If I have done this and I find the Buddha's teaching
acceptable, what would I do then if I wanted to become a Buddhist?

It would be best to join a good temple or Buddhist group,
support them, be supported by them and continue to learn more
about the Buddha's teachings. Then, when you are ready, you would
formally become a Buddhist by taking the Three Refuges.

What are the Three Refuges?

A refuge is a place where people go when they are distressed
or when they need safety and security. There are many types of
refuge. When people are unhappy, they take refuge with their friends,
when they are worried and frightened, they might take refuge in
false hopes and beliefs. As they approach death, they might take
refuge in the belief in an eternal heaven. But, as the Buddha
says, none of these are true refuges because they do not give
comfort and security based on reality.

Truly these are not safe refuges, not the refuge supreme. Not
the refuge whereby one is freed from all sorrow But to take refuge
in the Buddha, the Dhamma and the Sangha and to see with real
understanding the Four Noble Truths, Suffering, the cause of suffering,
the transcending of suffering and the Noble Eightfold Path that
leads to the transcending of suffering, This indeed is a safe
refuge, it is the refuge supreme. It is the refuge whereby one
is freed from all suffering.
Dp. 189-192

Taking Refuge in the Buddha is a confident acceptance of the
fact that one can become fully enlightened and perfected just
as the Buddha was. Taking Refuge in the Dhamma means understanding
the Four Noble Truths and basing one's life on the Noble Eightfold
Path. Taking Refuge in the Sangha means looking for support, inspiration
and guidance from all who walk the Noble Eightfold Path. Doing
this one becomes a Buddhist and thus takes the first step on the
path towards Nirvana.

What changes have taken place in your life since you
first took the three refuges?

Like countless millions of others over the last 2500
years, I have found that the Buddha's teachings have made sense
out of a difficult world, they have given meaning to what was
a meaningless life, they have given me a humane and compassionate
ethics with which to lead my life and they have shown me how I
can attain a state of purity and perfection in the next life.
A poet in ancient India once wrote of the Buddha:

To go to him for refuge, to sing his praise, to do him honor
and to abide in his Dhamma is to act with understanding. I agree
with these words completely.

I have a friend who is always trying to convert me
to his religion. I am not really interested in his religion and
I have told him so but he won't leave me alone. What can I do?

The first thing you must understand is that this person
is not really your friend. A true friend accepts you as you are
and respects your wishes. I suspect that this person is merely
pretending to be your friend so he can convert you. When people
try to impose their will on you they are certainly not friends.

But he says he wants to share his religion with me.

Sharing your religion with others is a good thing. But
I suggest that your friend doesn't know the difference between
sharing and imposing. If I have an apple, I offer you half and
you accept my offer, then I have shared with you. But if you say
to me "Thank you, but I have already eaten" and I keep
insisting that you take half the apple until you finally give
in to my pressure, this can hardly be called sharing. People like
your 'friend' try to disguise their bad behavior by calling it
'sharing', 'love' or 'generosity' but by what- ever name they
call it, their behavior is still just rude, bad manners and selfish.

So how can I stop him?

It is simple. Firstly, be clear in your mind what you
want. Secondly, clearly and briefly tell him so. Thirdly, when
he asks you questions like "What is your belief on this matter"
or "Why don't you wish to come to the meeting with me",
clearly, politely and persistently repeat your first statement.
"Thank you for the invitation but I would rather not come".
"Why not?" "That is really my business. I would
rather not come." "But there will be many interesting
people there." "I am sure there will be but I would
rather not come." "I am inviting you because I care
about you." "I am glad you care about me but I would
rather not come." If you clearly, patiently and persistently
repeat yourself and refuse to allow him to get you involved in
a discussion he will eventually give up. It is a shame that you
have to do this, but it is very important for people to learn
that they cannot impose their beliefs or wishes upon others.

Should Buddhists try to share the Dhamma with others?

Yes, they should. And I think most Buddhists understand the difference
between sharing and imposing. If people ask you about Buddhism,
tell them. You can even tell them about the Buddha's teachings
without their asking. But if, by either their words or their actions,
they let you know that they are not interested, accept that and
respect their wishes. It is also important to remember that you
let people know about the Dhamma far more effectively through
your actions than through preaching to them. Show people the Dhamma
by always being considerate, kind, tolerant, upright and honest.
Let the Dhamma shine forth through your speech and actions. If
each of us, you and I, know the Dhamma thoroughly, practice it
fully and share it generously with others, we can be of great
benefit to ourselves and others also.